Cleaning composition for removing sludge from internal-combustion engines



' Patented Apr. 15, 1947 CLEANING COMPOSITION FOR REMOVING SLUDGE FROM INTERNAL-COMBUSTION ENGINES George M. Skinner, Kenmore, N. Y., assignor to National Carbon Company, Inc., a corporation of New York No Drawing. Original application April 8, 1942, Serial No. 438,077, now Patent No. 2,403,618, dated July 9, 1946. Divided and this application October 2, 1945, Serial No. 619,902

3 .Claims. 1

The invention relates to the cleaning of metal surfaces, and is particularly concerned with liquid cleaner compositions for removing sludge deposits from the interior parts of internal combustion engines.

Under ordinary operating condit ons of an internal combustion engine there is usually formedv in the crank case, "on the surfaces of the combustion chamber, and on other interior working parts, a precipitate or deposit commonly referred to as e. This sludge is formed in large part of decompos tion produc s of ol and fuel used in the engine, and may be composed of heavyhydrocarbons, asphaltenes, gums, fine carbon, road dirt and other solid deposits. The sludge accumulates on, and becomes tightly bound to, the piston head and rings. the valve stems and the bearings, and in sufficiently large amounts it may markedly interfere with satisfactory engine operation. The removal of this sludge occas onally is, therefore, desirable, and While efforts have been made to accomplish this by means of various types and kinds of solvent cleaners, the matter of satisfactorily cleaning engines in a quick and easy manner remains a difficult and important problem.

It is an object of this invention to provide improved metal cleaner compositions, adapted more effectively, more readily, and more conveniently to remove sludge deposits from internal combustion engines.

The new cleaner is composed of a plurality of components, in controlled volume proportions to produce a homogeneous liquid mixture of exceptionally rapid and eifective cleaning action. As the essential loosening and dissolving agent for the sludge deposits, one or more organic solvents are used in an amount comprising at least 50% by volume of the total mixture. Water in an amount from about 4% to 25% of the whole, and oil in quantities preferably not exceeding about 39% by volume are mixed with the solvent, and a coupling agent is then added to produce a stable and homogeneous liquid composition. A detergent may also be included, but by preference the coupling agent selected is one which also will exert a detergent action.

Suitable solvents for this cleaner may be selected from organic ester compounds, and the best results have been obtained with mixtures of two or more solvents. The heterogeneous nature of the sludge deposit appears to account for the fact that a single solvent does not usually dissolve or loosen the deposit as well as a mixture of two or more of them. Carboxylic acid esters. of glycol monoalkyl ethers are good solvent components, and the cleansing action of these compounds can be further improved by mixing them with a lower carboxylic acidalkyl ester, such as methyl amyl acetate. The most suitable proportions of each solvent in these mixtures can be readil deterto by volume.

Water in the cleaner formula substantially aids in loosening tightly bound sludge, and causes flak ng off of lacquer-type deposits, which might not otherwise be attacked by the solvent. At least 4% Water is necessary to improve the cleaner performance, and it preferably should not exceed 25% by volume. is to afford lubricating properties, and prevent rusting of the metal surfaces after cleaning. Ordinary mineral lubricating oils are satisfactory for this use, and the oil proportions preferably vary from about 15% to 25% by volume.

A coupling agent is necessary to render the oil-water-sclvent mixture homogeneous, and thereby insure proper functioning of the cleaner both as initially formulated and after storage in containers. Some of the solvents above mentioned may in themselves assist in coupling of the completed mixture, but a further additive and thus further improve the solvent efficiencyf Morpholine soaps, such as morpholine oleate and morpholine ricinoleate have proven especially effective as coupling and detergency agents. A fatty acid, such as oleic acid, may also be added in addition to the amine soap, if desired, and may aid in softening the lacquer-like hard deposits on valve stems, piston heads and rings. The amine soap proportions are generally between about 5% and 20% by volume, and the fatty acid, if used, preferably should not exceed about 10%.

A complete cleaner formula representative of the invention, which has proven particularly effective in the cleaning of automobile engines, is shown in the following table:

In the manner of use and application of these The purpose of an oil addition vantage liesin the ease and convenience with which satisfactory cleaning can be efi'ected. With an engine still in running order, a cleaning treatment may consist in slowly adding a pint or so of the sludge remover through the carburetor air intake while operating atai speed J'ust sufii-- cient to prevent stalling. In this process the cleaner is carried directly into the combustion chambers and is later expelled through, the exhaust manifold. Thus, the. valves; pistons, piston rings and combustion chambers are exposed to the cleaner, and the very small quantities of.

the cleaner which may passthe piston rings into the crank case, are not sufiicient tocause any deleterious action on, or dilution of, the crank case oil.

Where the sludging is very severe and the most 7 effective cleaning action i desired, the treatment above can be augmented by crank case cleaning. This is accomplished by draining the crank case and refilling it to normal level with the concentrated cleaner formula before starting addition of cleaner to the' carburetor. At the conclusion of the carburetor treatment, the crank case is again drained, and may be flushed with light oil. This combination treatment effects excellent cleaning of the crank case, inner engine surfaces, bearingsand oil passages, as well as all parts of the combustion chambers. In case of complete engine seizure by heavy sludge, introduction of the cleaner into the spark plug holes, followed by a period of soaking, is usually effective in loosening the deposits. Where overhauling or dismantling of the engine is necessary, the cleaner composition can, of course, be used in theordinary way, and will be found rapidly effective in cleaning all metal surfaces.

In the particular liquid mixtures proposed, consideration has also been given to factors such as toxicity and odor, flash point, corrosiveness, and attack on gasket materials. These formulae are satisfactory insuch respects, havin no odor that is obnoxious, and being entirely safe to handle under the ordinary precautions used in handling common solvents. They are not irritating to the skin, and they do not readily corrode metal'sor attack gasket material.

It will be understood, however, that the specific cleaner formula given is merely representative, and that numerous modifications in the various components, and their proportions, may be made with the advantages described. Such modifications are intended to be included within the broader scope of the invention. This application is a division of my copending application Serial No. 438,077, filed April 8, 1942, issued as Pat- ,ent NO. 2,403,618, on July 9, 1946.

I claim:

1. A cleanin composition for removing sludge from internal. combustion engines consisting of a homogeneous liquid mixture of a solvent composed of'an acetate ester of a glycol monoalkyl ether and methyl amyl acetate, in appreciable component proportions and in total amount of about 50% to by volume; a lubricating oil in an amount from about 15% to 25%; about 4% to 25% of water; and about 5% to 20% of a morpholine soap coupling agent.

2. A cleaning composition for removing sludge from internal combustion engines consisting of a homogeneous liquid mixture of a solvent composed of ethylene glycol monoethyl ether acetate and methyl amyl acetate, in appreciable component proportions and in total amount of at least 50% by volume; a mineral lubricating oil in an amount not exceeding 30%; at least 4% water; and about 5% to 20% of a morpholine soap coupling agent.

3. A cleaning composition for removing sludge from internal combustion engines comprising a homogeneous liquid mixture, in proportions by volume, of about 35% ethylene glycol monoethyl ether acetate, about 20% methyl amyl acetate, about 20% mineral lubricating oil, about 5% water, and about 20% morpholine oleate.

GEORGE M. SKINNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,128,685 Yates Aug. 30, 1938 2,259,872 Baldeschwieler et a1. Oct. 21, 1941 2,032,174 Johnson Feb. 25, 1936 1,822,886 Elderkin Sept. 15, 1931 1,787,789 Lovell et al Jan. 6, 1931 1,833,429 Lovell et al. Nov. 24, 1931 OTHER REFERENCES 7 Ind. and Eng. Chem., vol. 27, No. 8 (Aug. 1935), pages 867-871. Article entitled New Aliphatic Amines. 

